im sorry, but i feel kind of sad when everybody starts to have a stereotype about littlemonsters being a jerk to other artist. it's very contrary to Gaga's messages. Just saying.
She never said "no" to go on stage with mdna (contrary to what mdna said to her fans on stage... Why mdna victimized herself like that??! :/ ) She was busy and she also suggested a duet with mdna ! Gaga describes herself as her biggest fan :D